FI96486B - Blade structure for an indoor bandy stick or the like - Google Patents

Description

5 96486

Blade structure for floorball racket or similar.

Bladkonstruktion för en Innebandy-klubba eller motsvarande

The invention relates to a blade structure for a floorball racket or the like, which blade structure consists of an open structure of plastic material or the like comprising an edge reinforcement rotating around the circumference of the blade and a plurality of transverse ribs of the blade structure having through or substantially continuous openings between the ribs and the edge reinforcement 10. that the cross-sectional area of the blade structure in a section plane substantially perpendicular to the length of the blade is asymmetrical with respect to the length of the blade and the plane of symmetry at least with respect to the length of the blade.

15 The blades of floorball rackets are now invariably made of plastic material in a mold by injection molding. The manufacture uses a straight mold, as a result of which the blades of the rackets are straight. However, a straight-bladed club is hardly used, and players want a certain curvature on the club blade, depending on their handiness. Because the blade of the racket is open in construction including edge reinforcements 20 and ribs extending across the blade structure, and because an easy-to-handle plastic is used as the blade material, the desired curvature of the racket blade is readily available. The blade of the club is generally curved by heating the blade, for example by soaking it in hot water, hot air blowing or the like, after which the blade can be bent to the desired curvature. When the desired curvature is reached, the blade is allowed to cool, leaving the blade in this curved shape for at least some time. The blade structures used are generally symmetrical in cross-section so that there is an equal amount of material on each side of the vertical plane perpendicular to the cross-section and most generally even so that the shape of the cross-section on each side of said plane is similar. Due to the blade structure and the manufacturing technique used, the stability of the blade in the desired curvature is quite poor. Since there is an equal amount of material on each side of the blade and since the curvature of the blade causes compressive stress on one side of the blade and tensile stress on the opposite side, these generated stresses over time straighten the blade blade. As a result, the club blade must be re-bent to the desired curvature from time to time.

The object of the present invention is to provide a novel blade structure 5 for a floorball racket or the like, which avoids the disadvantages associated with the prior art solutions and which, by simple measures, achieves the desired curvature of the racket blade already at the stage of blade manufacturing. To achieve this, the invention is mainly characterized in that the asymmetry of the cross-section of the blade structure is traced in the region of the upper and / or lower edge of the blade to the edge reinforcement of the blade or in the immediate vicinity of the edge-10 reinforcement.

The invention achieves several advantages over the prior art, and of these advantages it is possible to highlight e.g. following. First, the invention uses the same manufacturing technique as in existing racket blades, so that the manufacturing cost-15 mixes are of the same order of magnitude as in current blade structures. Thus, according to the invention, the desired curves on the club blade can be made with a mold with a straight dividing plane. This, in turn, is a consequence of the asymmetrical cross-sectional area of the blade structure according to the invention, whereby different shrinkage of the plastic on opposite sides of the asymmetrical blade causes the blade 20 to warp. The stability of the curvature of the blade in the desired shape is considerably better than in previously known solutions in which the blade straightens over time. In the invention, the shape of the curvature of the blade can be controlled by changing the materials used and the spraying parameters. Furthermore, if replacement pieces are made in the mold used so that the asymmetry of the cross-sectional area is different at different points of the pallet, different curvature shapes can be obtained by exchanging replacement pieces using the same mold. Other advantages and features of the invention will become apparent from the following more detailed description of the blade structure of the invention.

The invention will now be described in detail with reference to the figures of the accompanying drawing.

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Figure 1 is a schematic side view of a floorball racket blade according to the invention.

Figures 2A, 2B and 2C show various alternative cross-sectional shapes of the blade structure taken from the platform of Figure 1 along the line A-A.

In Fig. 1, a racket blade according to the invention is generally indicated by reference numeral 1. According to the figure, the blade 1 is open in a known manner so that the blade 1 comprises an edge reinforcement 2 around the blade and transverse ribs 3 of the blade structure 10. Large gaps thus remain between the edge reinforcement 2 and the ribs 3. There may also be a very thin wall, e.g. 1-1.5 mm thick, between the edge reinforcement 2 and the ribs 3. Reference numeral 5 denotes a pin-like protrusion to which the rod arm is attached. In the side view according to Figure 1, the blade structure does not differ from the solutions according to the prior art.

15

Figures 2A, 2B and 2C show alternative cross-sectional shapes of the pallet 1 taken along line A-A in Figure 1. The essential characteristics of the pallet according to the invention appear from these figures showing the cross-sections of the pallet. As can be seen from Figures 2A, 2B and 2C, the cross-section of the blade is not symmetrical in shape or area, as in the prior art solutions 20, but the amount and shape of material on opposite sides of the blade length and height and thus perpendicular to the cross-sectional plane S is different. Figures 2A, 2B and 2C are intended to illustrate that said asymmetry in the blade structure can be arranged at different points in the cross-section, whereby the curvature shapes of the blade can be varied as desired. In Figures 2A and 2B the asymmetry is traced in the vicinity of the pallet edge reinforcement 2, while in Figure 2C said asymmetry is traced by adding material 4 between the ribs 3. As already pointed out above, this variation in asymmetry is achieved, for example, by using replacement pieces in the mold.

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The asymmetry of the cross-sectional area of the blade structure described above thus provides the desired curvature of the blade in the desired direction. Although the blade is manufactured by injection molding in a straight mold, the blade 1 of the racket curves in the direction of the symmetry plane S in the direction on which side there is more material.

5 One reason for this curvature of the blade is that the side of the blade with more material cools more slowly than the opposite side. Further, there is more tensile stress on the higher mass side, whereby this tensile stress causes the blade to curve in the direction of the larger mass, even if the blade is allowed to cool in the mold. The blade structure 1 may be asymmetrical along its entire length, or on the other hand, the asymmetry of the blade structure 10 may be produced at desired locations to provide the desired curvature. In the case where the blade structure is asymmetrical along its entire length, the asymmetry of the cross-section may be similar along the entire length of the blade, or the asymmetry may vary as desired along the length of the blade to provide the desired curvature.

15

The invention has been described above by way of example with reference to the figures of the accompanying drawing. However, the invention is not limited to the examples shown in the figures only, but the invention may be varied within the scope of the inventive idea defined in the appended claims.

20

Claims (6)

96486 A blade structure for a floorball racket or the like, the open structure consisting of an open structure of plastic material or the like, comprising an edge reinforcement (2) rotating about the circumference 5 of the blade (1) and a plurality of transverse ribs (3) with ribs (3) and there are through-openings or a substantially thin wall between the edge reinforcement (2) such that the cross-sectional area of the blade structure (1) in a plane substantially perpendicular to the blade length is asymmetrical with respect to the blade length 10 and the height symmetry plane (S); characterized in that the cross-sectional asymmetry of the blade structure (1) is arranged in the region of the upper and / or lower edge of the blade in the edge reinforcement (2) of the blade or in the immediate vicinity of the edge reinforcement. Blade structure according to Claim 1, characterized in that the cross-sectional asymmetry of the blade field (1) is formed by arranging between the ribs (3) running across the blade structure different amounts of blade material (4) on opposite sides of the plane of symmetry (S). Blade structure according to Claim 1 or 2, characterized in that the cross section of the blade structure is asymmetrical over substantially the entire length of the blade (1). Blade structure according to Claim 3, characterized in that the cross-sectional asymmetry of the blade field (1) is substantially equal over the length of the blade. Blade structure according to Claim 3, characterized in that the cross-sectional asymmetry of the blade structure (1) is different at different points along the length of the blade 30. 96486 Blade structure according to Claim 1 or 2, characterized in that the cross section of the blade structure (1) is formed asymmetrically in certain areas along the length of the blade, so that outside these areas the blade structure is symmetrical. 5 il. ··> * joined it t v * '- 96486